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Derivative And Credit-Related Financial Instruments (Schedule Of Financial Instruments With Off-Balance Sheet Credit Risk) (Details) - Maximum - USD ($) $ in Millions | Jun. 30, 2024 | Dec. 31, 2023
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Unused Commitments to Extend Credit |  |
Credit Related Financial Instrument [Line Items] |  |
Loss contingency, estimate of possible loss | $ 28,183 | $ 31,385
Commercial and other | Unused Commitments to Extend Credit |  |
Credit Related Financial Instrument [Line Items] |  |
Loss contingency, estimate of possible loss | 24,130 | 27,303
Bankcard, revolving credit and home equity loan commitments | Unused Commitments to Extend Credit |  |
Credit Related Financial Instrument [Line Items] |  |
Loss contingency, estimate of possible loss | 4,053 | 4,082
Standby letters of credit |  |
Credit Related Financial Instrument [Line Items] |  |
Loss contingency, estimate of possible loss | 3,754 | 3,586
Commercial letters of credit |  |
Credit Related Financial Instrument [Line Items] |  |
Loss contingency, estimate of possible loss | $ 49 | $ 48

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